I wonder whether it's caused by default mixer settings in OSS, but after installing lates OSS port 4.0.b1012_3 on FreeBSD 7.0-RC1 (while switching from default sound and snd_hda modules), I've got an awful sound feedback between the internal mic of Lenovo T61p and it's speakers. This may fairly easy to turn off once you find out where it is, but it's definitely scaring for normal users.

Yes - maybe time to change those defaults, at least for routing the mic directly into the speakers. This is annoying feature for most of the apps anyway (except when you really need it for some testing, but then I'd say it's up to the application/user to turn this feedback on).

Btw, I've noted there might be some problem also with the driver as it says